Hi Will,
When we first got our engine running we checked the oil pump 'suction'
as was called out in the Europa build manual in the engine
provisioning(?) section. We found the suction to be too great, I'm at
work now and don't remember the exact numbers. We observed that the
Europa supplied oil line from the oil cooler to oil pump inlet had a
molded 90 deg bend in it, a few inches before the pump inlet, and
suspected that the oil line was partially collapsing at this bend. We
replaced the molded elbow with a short section of 90 deg aluminum
tubing. A subsequent oil pump suction test showed a drop in suction,
bringing if fairly close to the specified maximum value. The suction
values were, as expected, greatest when the oil was cold, and dropped
off as the oil warmed up. I would expect that the elbow in the oil line
feeding the pump inlet would be most likely to collapse when the oil is
cold and the suction is at its greatest.
At the time (about six years ago) we sent emails to the Europa group
asking what values others were getting in their suction tests, but
received no responses from anyone who had performed the test. If there
is anyone who has performed the suction test, I would be interested in
hearing their numbers.
regards,
Terry Seaver
A135/N125TD
Monowheel XS with 912S, Whirlwind prop
________________________________
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of William
Daniell
Sent: Monday, April 23, 2007 9:53 AM
Subject: RE: Europa-List: Oil pressure
Sorry, I forgot to add that we have purged the system as per the latest
rotax bulletin and also checked the regulator.
Correct me if I am wrong but I have seen "burping" the system. I have
always assumed that this was rotating the prop in the correct direction
with the cap of the oil tank off until you get the burping sound. Is
this correct?
The only thing that I can think of is that it is some kind of
restriction in the "circuit" which ceases to be a restriction once the
oil is less viscous (warmed up).
Will
________________________________
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Jerry Rehn
Sent: Monday, April 23, 2007 11:27
Subject: RE: Europa-List: Oil pressure
You could test the oil system per SI-912-005. This would help determine
problems of suctions and pressures. Also you might try purging the
system per SI-04-1997. This is relatively easy to do and would insure
there isn't air in your system. Third check the oil relief ball and
spring for wear and contamination another easy check.
Jerry
________________________________
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of William
Daniell
Sent: Monday, April 23, 2007 8:18 AM
Subject: Europa-List: Oil pressure
I know that I have asked this before but I wonder if everyone could rack
their brains.
My motor starts fine the pressure goes up to 5.5 bar for about 2-4
minutes.
It then falls with not loss of rpm to 1.5 bar for about 2-5 minutes.
It then goes back up to 5.5 and stays there without a problem.
The oil pressure sender is working fine and is the gauge - I have tested
them both. The engine runs smooth and produces sufficient power. I run
avgas because the premium mogas here is 95 or lower octane.
On a hot day the pressure drop is minimal on start up. So I am thinking
that maybe this has something to do with viscosity. Perhaps even what
Ira mentioned - lead accumulation in the oil tank.
Any ideas as to the cause?
How much damage will this do? Clearly this is not ideal but it could be
one of those problems where the "solution" ends up being always out of
reach.
Will
Colombia
|